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Installation of 4.0 FI on 258 - Any Sites Available

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I interested if there are any sites available that detail the steps involved in installing a FI system from a 91-95 4.0 on a 80-85 CJ. I have read the discussion threads about this conversion, but interested if its been put together and further explained? Appreciate recommendation.

It's too cold up here to do anything else. The CJ started this morning after 40-50 pumps and another 10-15.

MindBender

Mindbender
CJ7 258
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There is the Howell EFI and the Mopar. The Howell will run you about $1k and the Mopar is about $2k. The difference is that the Mopar
includes the distributor and other stuff. The Howell is just the throttle body, computer, and a few other things.

Before you dive into the fuel injection, try the GM HEI distributor upgrade. I am in the process of getting the parts. I have heard GREAT
things about this conversion.

Check out these links:
http://www.geocities.com/Baja/Outback/4485/hei_1_stock.htm
http://www.best.com/~sanchez/HEI/HEI.htm

Good Luck

O|||||O
A conclusion is simply the place where you got tired of thinking.
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I have a neighbor that had the 4.0 FI installed on his CJ7. It was a somewhat custom job but it seems to work great - well worth it.

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Actually, I have put the 4.0 head on the 258. What I am looking for is a step by step guide for installing a EFI from a 90s jeep onto the 4.0 on my 85 CJ. Planning on this as a Spring Project. I am aware of the suggestion to get the manuals with specs for electonics on both jeeps when hooking up the wires. Although concerned about the wiring, my first concerns are related to the installation and use of the various sensors that are required to install the EFI. I have looked at Tim's site on the Mopar system, but I not sure how comparable that is to taking an EFI off a 90s jeep and installing in on the 85. Thanks, WES

Mindbender
CJ7 258
It is pretty straight forward, just like wiring up a stock yj or xj. The only part that may cause a problem would be the crank angle sensor. The easiest way around this would be to use the harmonic balancer from the Mopar spfi kit. It would also be nice to use the alternator and serpentine drive from the 4.0, that way you won't get false codes for charging. Remember, if you do, you must use the 4.0's water pump, as it turns the other direction. I used a stock harness from a wrecked xj, clamped the 60 pin connector in a vise, and cut the harness back. Using a wiring diagram from a xj, I cut out all the wires that I didn't need, such as cruise control inputs. I designed it so there was only 6 wires to hook up, ground, key on power, always live power, start signal, check engine lamp, and fuel pump out. I also wired in two relays, the A.S.D. and the fuel pump, I wired around the fuel pump ballest circuit. Also remember to brake out the two wires for the vehicle speed sensor.

The second harness I built for a friends '83 CJ-7, I used the power distributation center for the relays. This worked out much nicer than mine, as I wired up auxiliary lighting from this panel, and used it for the A.S.D. and fuel pump relays. Another tip that may help, try to use a pcm from a '94 or '95, as these have better block learn, and will more capable of correcting the amount of fuel for the larger displacement engine.


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Thanks, John. Those are helpful suggestions. Appreciate your comments. If you ever do the setup again, it would be great if you could document step by step how to's for use of limited mechanical and electrical knowledge. Thanks, Mindbender

Mindbender
CJ7 258
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I installed a HEI and my engine now works great, smooth, quiet... Im now installing a 4bbl intake and a 350cfm 4bbl carburator, the next will be a new camshaft...

Jchio
www.alloffroad.com

Jchio
icq # 18428174
www.alloffroad.com
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